2d2 



SCIENCE. 



[N. S. Vol. XIX. No. 476. 



ent one deals witli economic minerals strictly, 

 exclusive of metallic ores, and in the main of 

 precious and ornamental stones. 



The plan of the work is good, and the geolog- 

 ical element in it is valuable; but the treat- 

 ment is very unequal, some portions being well 

 and fully presented, and others but inade- 

 quately. The work bears no date, and t'akes 

 no note of some important recent develop- 

 ments, e. g., that of monazite and the related 

 rare earths. Its chemical formulas, too, are 

 not modern. As a whole, the book is of inter- 

 est in its suggestion of what might be, if the 

 author's ideas were carried out more fully and 

 comprehensively, errors and omissions cor- 

 rected, and the treatment brought up to date. 



G. F. K. 



SOCIETIES AND ACADEMIES. 

 ONONDAGA ACADEMY OF SCIENCE. 



At the October meeting of the academy, 

 held in the Syracuse high school building. 

 Dr. T. C. Hopkins presented an illustrated 

 paper on the glaciers of Switzerland and 

 Austria. The paper was based on field studies 

 in the Alps during the past summer. It illus- 

 trated many features of the Alpine glaciers 

 such as the snow fields, aiguilles, crevasses, 

 moraines, gorges and the marked recession of 

 many of the glaciers in recent years. 



At the November meeting of the academy, 

 held in the historical society rooms there were 

 three papers on biological subjects : 

 1. Diseases of Cultivated Flowering Plants: 



George T. Hargitt. 



The diseases were classified, according to the 

 function disturbed, into three classes : 



(a) Disturbed PJwtosynthesis. — The rusts 

 are one of the commonest diseases of plant 

 life and in the carnations it is caused by the 

 fungus Uromyces caryophyllinus, one of the 

 most serious diseases of this plant. Darluca 

 filum, usually occurring in connection with 

 this rust, is commonly considered as parasitic 

 on the rust, but investigations seem to show 

 it rather to be parasitic on the carnation. 

 Plants affected by both the rust and Darluca 

 are in worse condition than those affected only 

 by the rust. The disease ' white legs ' of the 

 aster results in dwarfing, malformation and 



final decay. It is caused by nematode worms 

 of the genus Heterodera or perhaps Aphenen- 

 chus. Leaf spot diseases, common in a great 

 many plants, are caused by a number of dif- 

 ferent fungi. 



(6) Disturhed Transpiration. — The rusts 

 also cause a disturbance of the transpiration, 

 which is usually the more destructive, due to 

 the unguarded evaporation of water through 

 the ruptures in the epidermis caused by the 

 liberatifja of the spores. In carnations a dis- 

 ease called stigmonose is caused by the punc- 

 tures of insects. 



(c) Interference with the Supply or Absorp- 

 tion of Water. — The most destructive disease 

 of this type is the aster wilt or stem rot. The 

 characteristic effect is a wilting and a yellowish 

 color first seen on one side of the plant, usually 

 in one of the lower leaves. It is caused by 

 the growth of a Fu^arium .iungus in the large 

 water-carrying vessels, which are thus gradu- 

 ally clogged up. A more elaborate paper on 

 this subject by Mr. Hargitt appears in the re- 

 port of the Nebraska State Horticultural So- 

 ciety for 1903. 

 2. Some Features of the Development of 



Flowering Plants: Dr. J. E. Kirkwood. 



The paper embodies the results obtained 

 from the study of the embryology of about 

 fifteen species of the Cucurbitaceffi. In all 

 the forms examined the ovary begins by the 

 invagination of a lateral shoot and the organs 

 of the flower appear in the following order: 

 sepals, petals, staminodia (when present) and 

 carpels. In the early stages of embryonic 

 growth the endosperm p'lays an important part 

 by digesting the nucleus and nourishing the 

 embryo. 

 •3. Bithynia tentaculata: Albert J. May. 



The gastropod Bithynia tentaculata was in- 

 troduced into the United States froia' Europe 

 and has become very abundant in New York. 

 It was first noticed in this country in 1879, 

 when specimens were taken simultaneously at 

 Oswego and in the Champlain canal near Troy. 



They seem to multiply and spread very 

 rapidly. They are now reported from points 

 all along the Hudson Eiver and the Erie 

 Canal. They are abundant in the Genesee 

 and Niagara Rivers. 



